KR101514098B1 - Plasma processing apparatus and temperature measuring method and apparatus used therein - Google Patents

Abstract

A plasma processing apparatus, a temperature measuring method, and a temperature measuring apparatus capable of accurately measuring the temperature of a substrate and the like, and capable of performing plasma processing of a substrate with higher precision and efficiency. A vacuum chamber 2, a mounting table 3 and a base plate 9 spaced apart from the mounting table 3 below the mounting table 3 and temperature measuring means, 3 is placed in a vacuum atmosphere, and a space between the mounting table 3 and the base plate 9 becomes a normal pressure atmosphere. The upper and lower surfaces of the mounting table 3 are optically communicated with each other so that the measurement light of the temperature measuring means can be transmitted and the hermetically sealed temperature measurement windows 12 to 15 are provided. And a connecting member 30 for connecting them to the plate 9 is provided.

Description

TECHNICAL FIELD [0001] The present invention relates to a plasma processing apparatus, a plasma processing apparatus,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma processing apparatus, a temperature measuring method, and a temperature measuring apparatus for processing a substrate, for example, a semiconductor wafer or a substrate for a liquid crystal display apparatus using plasma.

Accurately measuring the temperature of a substrate to be processed by the plasma processing apparatus, for example, a semiconductor wafer or a substrate for a liquid crystal display apparatus is performed on a substrate for a semiconductor wafer or a liquid crystal display by various processing results such as film formation or etching It is extremely important to precisely control the shape, physical properties, etc. of a film or a hole. For this reason, it is conventionally performed to measure the temperature of a semiconductor wafer or a substrate for a liquid crystal display by various methods such as a resistance thermometer and a measurement method using a fluorescent thermometer for measuring the temperature on the back surface of the substrate.

Recently, a temperature measuring technique using a low coherence interferometer capable of directly measuring the temperature of a substrate, which is difficult in the conventional temperature measuring method as described above, is known. Further, in the temperature measuring technique using the low coherence interferometer, the light from the light source is split by the first splitter into the measurement light for temperature measurement and the reference light by the first splitter, and the measurement light divided by the second splitter is divided into n measurement light N measurement light beams are divided into n measurement points and the interference between the reflected light of the n measurement lights and the reflected light of the reference light reflected by the reference light reflecting means is measured to measure the temperatures of the plurality of measurement points simultaneously (For example, refer to Patent Document 1). According to this technique, the temperature of a plurality of measurement points can be measured at a time with a simple configuration.

[Patent Document 1] Japanese Patent Application Laid-Open No. 2006-112826

When the temperature of the substrate under processing is measured by the plasma processing apparatus using the temperature measuring apparatus having the above-described low coherence interferometer, the substrate is placed in a vacuum chamber mounted on a mounting table and in a vacuum atmosphere. On the other hand, the collimator provided at the exit of the optical fiber for guiding the measurement light is fixed to the outside of the base plate of the vacuum processing chamber, which is normally kept at an atmospheric pressure atmosphere, in consideration of the maintenance aspect such as optical axis alignment.

Here, the mount table on which the above-described substrate is mounted is constituted by an electrostatic chuck for attracting a substrate and an RF plate for applying high-frequency power, and these constituent members are structured to substantially divide a vacuum atmosphere and an atmospheric pressure atmosphere have. In the lower part of the mounting table, there is a space sufficient for inserting the RF plate and the base plate, or a semiconductor wafer is mounted on the mounting table from the transfer arm, or the semiconductor wafer is lifted from the mounting table, A space for providing a drive mechanism of the drive plate is required. Therefore, there is a case where a space is formed to some extent between the mount table and the base plate.

In such a configuration, the mounting table may be bent due to a pressure difference between the vacuum and the atmospheric pressure, or vibration may occur in the mounting table due to the influence of the temperature adjusting medium for cooling and the like flowing in the mounting table. As a result, it has been found that there is a problem that the gap between the collimator and the substrate mounted on the object to be mounted is fluctuated and accurate temperature measurement is not performed. Further, it has been found that there is a problem that the space between the RF plate and the base plate is in a standby state, and the fluctuation of the air affects the optical path to deteriorate the measurement accuracy.

The problem that the fluctuation of the air affects the optical path and the measurement accuracy deteriorates is also a problem when measuring the temperature of the focus ring provided in the plasma processing apparatus.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and it is an object of the present invention to provide a plasma processing apparatus capable of measuring the temperature of a substrate or the like with high precision and capable of performing plasma processing of a substrate with high precision and efficiency, And to provide a measuring device.

A plasma processing apparatus according to a first aspect of the present invention includes: a vacuum chamber for accommodating a substrate and processing the plasma by a plasma; a mount table provided in the vacuum chamber and on which a substrate is mounted; A base plate, a light source, a splitter for dividing the light from the light source into measurement light and reference light, reference light reflection means for reflecting the reference light from the splitter, An optical fiber for irradiating the measurement light to the substrate, a collimator provided at an exit portion of the optical fiber, and a collimator for measuring interference between the measurement light reflected from the substrate and the reference light reflected from the reference light reflection means, Temperature measurement with photodetector for measurement Wherein the upper surface of the mount table is in a vacuum atmosphere and the distance between the mount table and the base plate is a normal pressure atmosphere, wherein the upper surface and the lower surface of the mount table are configured to allow the measurement light to pass therethrough A window for optically communicating and hermetically sealed temperature measurement is provided and a member for connecting the mounting table to the base plate is provided at an interval between the mounting table and the base plate, A collimator is fixed at a position corresponding to the window for temperature measurement of the base plate and a rod or hollow through which the measurement light can pass is inserted into the optical path of the measurement light between the mount table and the base plate, ) From the temperature measurement window to the temperature measurement means Characterized in that a possible measuring the temperature of the substrate.

The plasma processing apparatus according to claim 2 is characterized in that, in the plasma processing apparatus according to claim 1, the mounting table is provided with a mirror or a prism for bending the optical path of the measurement light sideways and vertically, And the temperature of the upper portion of the portion where the structure exists is measurable.

According to a third aspect of the present invention, there is provided a plasma processing apparatus comprising: a vacuum chamber for receiving and processing a substrate by plasma; A mount table provided in the vacuum chamber and on which a substrate is mounted; A base plate provided below the mount table and spaced apart from the mount table; A reference light reflecting means for reflecting the reference light from the splitter; and an optical path length changing means for changing the optical path length of the reference light reflected from the reference light reflecting means, An optical fiber for irradiating the measurement light onto the substrate, a collimator provided at an exit portion of the optical fiber, and a collimator for measuring the interference between the measurement light reflected from the substrate and the reference light reflected from the reference light reflection means. And a temperature measuring means having a detector, wherein the upper part of the mounting table is in a vacuum atmosphere, and a space between the mounting table and the base plate is atmospheric pressure, characterized in that the upper surface and the lower surface of the mounting table So that the measurement light can be transmitted And a member for connecting the mounting table to the base plate is provided at an interval between the mounting table and the base plate, The temperature of the substrate is measured by the temperature measurement means from the temperature measurement window and the temperature of the substrate is measured by the temperature measurement means, A mirror or a prism for bending toward the side and the up and down direction is provided and the temperature of a portion above the portion where the structure exists between the mount table and the base plate can be measured.

According to a fourth aspect of the present invention, in the plasma processing apparatus according to the first aspect of the present invention, the mounting table includes an RF plate made of a conductive material to which high frequency power is applied, And a chuck.

The plasma processing apparatus according to claim 5 is characterized in that in the plasma processing apparatus according to claim 4, the RF plate and the electrostatic chuck are fixed at both the peripheral portion and the central portion.

According to a sixth aspect of the plasma processing apparatus of the present invention, in the plasma processing apparatus according to the first aspect, the mounting table is characterized in that an RF plate made of a conductive material to which high frequency power is applied and an electrostatic chuck for adsorbing the substrate are integrally formed do.

A plasma processing apparatus according to a seventh aspect of the present invention is a plasma processing apparatus comprising a vacuum chamber for accommodating a substrate and processing the plasma by plasma, a mount table provided in the vacuum chamber for mounting the substrate thereon, A reference beam reflecting means for reflecting the reference beam from the splitter; and a beam splitting means for splitting the reference beam reflected from the reference beam reflecting means into a beam path length An optical fiber for irradiating the measurement light to the substrate, a collimator provided at an exit portion of the optical fiber, and a collimator for measuring interference between the measurement light reflected from the substrate and the reference light reflected from the reference light reflection means A temperature measurement including a photodetector for measuring the temperature Wherein the upper part of the mounting table is in a vacuum atmosphere and the interval between the mounting table and the base plate is a normal pressure atmosphere, And the collimator is fixed at a position corresponding to the temperature measurement window of the mount table, and the temperature measurement window So that the temperature of the substrate can be measured.

The plasma processing apparatus according to claim 8 is the plasma processing apparatus according to claim 7, wherein the mounting table comprises: an RF plate made of a conductive material to which high frequency power is applied; and an electrostatic chuck And the collimator is fixed to the RF plate or the electrostatic chuck.

According to a ninth aspect of the present invention, in the plasma processing apparatus according to the seventh aspect, the mounting table has a configuration in which an RF plate made of a conductive material to which high-frequency power is applied and an electrostatic chuck for adsorbing the substrate are integrated, And the collimator is fixed to the RF plate.

In the plasma processing apparatus according to claim 10, in the plasma processing apparatus according to claim 7, the temperature measuring means includes a second splitter for dividing the measurement light from the splitter into n first to n-th measurement lights And the temperature of a plurality of portions can be measured by a plurality of measurement lights from the second splitter.

The plasma processing apparatus according to claim 11 is characterized in that, in the plasma processing apparatus according to claim 7, an opposing electrode is provided in the vacuum chamber so as to face the mounting table, The temperature of the portion of the counter electrode can be measured through the substrate of the counter electrode.

The plasma processing apparatus of claim 12 includes: a vacuum chamber for receiving and processing by plasma a substrate; A mount table provided in the vacuum chamber and on which a substrate is mounted; A base plate provided below the mount table and spaced apart from the mount table; A reference light reflecting means for reflecting the reference light from the splitter; and an optical path length changing means for changing the optical path length of the reference light reflected from the reference light reflecting means, An optical fiber for irradiating the measurement light onto the substrate, a collimator provided at an exit portion of the optical fiber, and a collimator for measuring the interference between the measurement light reflected from the substrate and the reference light reflected from the reference light reflection means. And a temperature measuring means having a detector, wherein the upper part of the mounting table is in a vacuum atmosphere, and a space between the mounting table and the base plate is atmospheric pressure, characterized in that the upper surface and the lower surface of the mounting table So that the measurement light can be transmitted And a member for connecting the mounting table to the base plate is provided at an interval between the mounting table and the base plate, Wherein the substrate is fixed at a position corresponding to the temperature measurement window of the base plate so that the temperature of the substrate can be measured from the temperature measurement window by the temperature measurement means, And the temperature measuring means is capable of measuring the temperature of the portion of the counter electrode through the temperature measurement window and the substrate of the object to be mounted.

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According to the present invention, it is possible to provide a plasma processing apparatus, a temperature measuring method, and a temperature measuring apparatus capable of accurately measuring the temperature of a substrate or the like, and performing plasma processing of a substrate with higher precision and efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view showing a main part cross-sectional configuration of a plasma processing apparatus according to an embodiment of the present invention;
FIG. 2 is an enlarged view of a main configuration of the plasma processing apparatus of FIG. 1,
FIG. 3 is a block diagram showing a schematic configuration of a temperature measuring means of the plasma processing apparatus of FIG. 1;
4 is a diagram for explaining the state of reflection of measurement light,
5A and 5B are diagrams for explaining an example of an interference waveform,
6A and 6B are diagrams showing an example of temperature measurement results in the plasma processing apparatus of FIG. 1,
7 is a schematic view showing a main part cross-sectional configuration of a plasma processing apparatus according to another embodiment of the present invention,
FIG. 8 is a schematic sectional configuration of a principal part of a plasma processing apparatus according to another embodiment of the present invention,
FIG. 9 is a schematic view showing a main part cross-sectional configuration of a plasma processing apparatus according to another embodiment of the present invention;
FIG. 10 is a view showing a schematic sectional configuration of a principal part of a plasma processing apparatus according to another embodiment of the present invention,
11 is a schematic view showing a main part cross-sectional configuration of a plasma processing apparatus according to another embodiment of the present invention,
FIG. 12 is a view showing a schematic sectional configuration of a main part of a plasma processing apparatus according to another embodiment of the present invention,
13 is a schematic view showing a main part cross-sectional configuration of a plasma processing apparatus according to another embodiment of the present invention,
14 is a view for explaining a state of reflection of measurement light from a cell,
15 is a view for explaining a state of reflection of measurement light from a cell,
16A and 16B are diagrams for explaining an example of an interference waveform,
17 is a flowchart showing a procedure for performing temperature measurement of a cell,
18A and 18B are diagrams showing an example of the temperature measurement result of the cell and the focus ring,
19A to 19H are views showing the configuration of a modified example of the window for temperature measurement,
20A and 20B are diagrams showing a configuration of a modified example of the window for temperature measurement,
FIG. 21 is a diagram showing a schematic sectional configuration of a principal part of a plasma processing apparatus according to another embodiment of the present invention;
FIG. 22 is a view schematically showing the configuration of a principal part of a main part of a plasma processing apparatus according to another embodiment of the present invention;
23 is a view showing a schematic configuration of a recessed portion viewed from the side of a plasma processing apparatus according to a modified example of the present invention,
Fig. 24 is a diagram showing a schematic configuration of the recess of the plasma processing apparatus of Fig. 23 viewed from above. Fig.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the present specification and drawings, constituent elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

Fig. 1 is a diagram schematically showing the configuration of the main part of the main part of the plasma processing apparatus 1 according to the present embodiment. As shown in Fig. 1, the plasma processing apparatus 1 includes a vacuum chamber 2 for receiving a semiconductor wafer W as a substrate and treating the semiconductor wafer W by plasma.

In the vacuum chamber 2, a mounting table 3 for mounting a semiconductor wafer W is provided. The mounting table 3 is made of a conductive material and includes an RF plate 4 to which high frequency power is applied and an electrostatic chuck 5 provided on the RF plate 4 for adsorbing the semiconductor wafer W And a power feed rod 6 electrically connected to a high frequency power source (not shown) is connected to a central portion of the RF plate 4. [

An annular baffle plate 7 is provided around the mount table 3 so as to surround the mount table 3. The lower surface of the mount plate 3 is provided with uniform An annular exhaust space 8 for exhausting the exhaust gas is formed. A base plate 9 is provided at the bottom of the vacuum chamber 2 and an air gap 10 is formed between the RF plate 4 and the base plate 9. The gap 10 is wide enough to insulate the RF plate 4 and the base plate 9 from each other. A driving device (not shown) of a pusher pin for receiving the semiconductor wafer W from the transfer arm and mounting it on the stage 3 or for lifting the semiconductor wafer W from the stage 3 and delivering it to the transfer arm, Is installed in the gap (10). Further, the space 10 is not an atmosphere of vacuum but an atmosphere.

An opposing electrode 11 is provided above the mounting table 3 so as to face the mounting table 3 with a gap therebetween. The counter electrode 11 is constituted by a so-called showerhead and is configured to be able to supply a predetermined process gas to the semiconductor wafer W mounted on the mount table 3 in the form of a shower. The counter electrode 11 is grounded or high frequency power is applied. Further, a focus ring 29 is provided around the semiconductor wafer W on the mounting table 3. This focus ring 29 is intended to improve the in-plane uniformity of the plasma treatment of the semiconductor wafer W.

The vacuum chamber 2 is configured such that the space above the loading table 3 is in a vacuum atmosphere and the space 10 under the loading table 3 is in a normal pressure atmosphere. Therefore, the stage 3 constitutes a part of the dividing wall dividing the vacuum atmosphere and the atmospheric pressure atmosphere. A plurality of (four in the example shown in Fig. 1) temperature measurement windows 12 to 15 are formed on the mount table 3. These temperature measurement windows 12 to 15 are optically communicated and hermetically sealed so that measurement light can be transmitted through the upper surface and the lower surface of the mounting table 3.

In the present embodiment, the temperature measurement window 15 provided at the outermost position of the mounting table 3 among the temperature measurement windows 12 to 15 is for measuring the temperature of the focus ring 29 And the remaining windows 12 to 14 for temperature measurement are for measuring the temperature of the semiconductor wafer W.

Fig. 2 is an enlarged view of the configuration of the windows 12 to 15 for temperature measurement. A through hole 50 penetrating the RF plate 4 and a through hole 51 penetrating the electrostatic chuck 5 are provided on the mounting table 3 as shown in Fig. A large diameter portion 51a having an enlarged inner diameter is provided at the lower end of the through hole 51 of the electrostatic chuck 5. An upper end of the through hole 50 of the RF plate 4 has a diameter The inclined surface 50a is formed.

A flange 52a protruding outward from the lower end of the through hole 51 of the electrostatic chuck 5 is formed in a substantially cylindrical shape and a groove 52d is formed along the inner periphery of the flange 52a. A sleeve 52 is formed. The sleeve 52 is made of ceramic, resin, alumite or the like. The sleeve 52 and the through hole 50 of the RF plate 4 are made of a material capable of transmitting measurement light (infrared rays) for temperature measurement, for example, quartz or sapphire, The formed window member 53 is inserted. The window member 53 has a large diameter portion 53a at the lower end thereof, that is, inside the through hole 50 of the RF plate 4, and the upper surface of the large diameter portion 53a and the lower end of the sleeve 52 And the inner periphery is brought into contact with each other, thereby positioning them correctly.

An O-ring 54 for vacuum sealing is provided on the large-diameter portion 53a of the window member 53. The O-ring 54 for the vacuum seal has a large-diameter portion 53a, a bottom surface of the sleeve 52, And the inclined surface 50a on the side of the RF plate 4 so as to maintain airtightness. An O-ring 55 is provided in the groove 52d of the flange 52a of the sleeve 52 to prevent the window member 53 from flowing down. A cylindrical buffer member 56 is provided in the through hole 50 so as to be in contact with the outer circumference of the lower surface of the large diameter portion 53a of the window member 53. [

A protective film 57 made of a ceramic plate, a polyimide film, a thermal sprayed film, an alumite, or sapphire is formed on the upper surface of the electrostatic chuck 5, An opening 58 having a diameter of about 1 mm to 3 mm, for example, is formed.

As shown in Fig. 1, through holes 16 to 19 are provided in the base plate 9 corresponding to the temperature measurement windows 12 to 15, respectively. And collimators 24 to 27 provided at the exit of the optical fibers 20 to 23 for guiding measurement light are fixed. The base plate 9 and the mounting table 3 (RF plate 4) are connected to the gap 10 between the base plate 9 and the mounting table 3 (RF plate 4) A connecting member 30 is disposed. Although only one connecting member 30 is shown in Fig. 1, a plurality of (for example, four or more) connecting members 30 are arranged along the circumferential direction. These connecting members 30 are for restraining the deformation and vibration of the mounting table 3.

The optical fibers 20 to 23 are connected to the temperature measuring means 100 configured as shown in Fig. 3, the temperature measuring means 100 includes a light source 110, a first splitter 120 for dividing the light from the light source 110 into reference light and measurement light for temperature measurement, A second splitter 130 for dividing the measurement light from the first splitter 120 into n first to n-th measurement lights (n = 4 in this embodiment), and a second splitter 130 for splitting the reference light from the first splitter 120 And an optical path length changing means 150 for changing the optical path length of the reference light reflected from the reference light reflecting means 140. The optical path length changing means 150 includes a reference light reflecting means 140 for reflecting the reference light,

The optical path length changing means 150 includes a linear stage 151 for moving the reference light reflecting means 140 constituted of a reference mirror or the like in one direction parallel to the incident direction of the reference light, a servomotor 152, a laser interferometer 153, and the like. Thus, by driving the reference light reflecting means 140 such as a reference mirror in one direction, the optical path length of the reference light reflected from the reference light reflecting means 140 such as a reference mirror can be changed. The servomotor 152 is controlled by the controller 170. Further, the signal from the laser interferometer 153 is converted into a digital signal by the A / D converter 172 and input to the controller 170.

When the first to fourth measurement lights are irradiated to the first to fourth measurement points of the semiconductor wafer W and the focus ring 29 or the like, The first to fourth measuring lights reflected from the ring 29 and the like and the optical detector for measuring the interference between the reference light and the reference light reflected from the reference light reflecting means 140 when the reference light reflecting means 140 is irradiated 160).

As the light source 110, any light can be used as long as the interference between the measurement light and the reference light can be measured. In order to measure the temperature of the semiconductor wafer W, at least the light reflected from the surface (usually about 800 μm to 1500 μm) between the front surface and the back surface of the semiconductor wafer W does not cause interference . Concretely, for example, low coherence light is preferably used. Low coherence refers to light with a short coherence length. The center wavelength of the low coherence light is preferably, for example, 0.3 탆 to 20 탆, more preferably 0.5 탆 to 5 탆. The coherence length is preferably, for example, 0.1 to 100 탆, more preferably 3 탆 or less. By using such low coherence light as the light source 110, it is possible to avoid interference due to excessive interference, and interference with the reference light based on the reflected light from the surface or the inner layer of the semiconductor wafer W can be easily Can be measured.

As the light source using the low coherence light, for example, an SLD (super luminescent diode), an LED, a high luminance lamp (a tungsten lamp, a xenon lamp, etc.), an ultra-wide wavelength light source, or the like can be used. Among these low coherence light sources, it is preferable to use SLD (wavelength, for example, 1300 nm) having a high luminance shown in Fig. 3 as the light source 110.

As the first splitter 120, for example, an optical fiber coupler is used. However, the present invention is not limited to this, and any measurement may be used as long as it can be divided into reference light and measurement light. Also for the second splitter 130, for example, an optical fiber coupler is used. However, the present invention is not limited to this, and any measurement may be used as long as it is possible to divide the measurement light into the first through fourth measurement lights. As the first splitter 120 and the second splitter 130, for example, an optical waveguide type demultiplexer or a half-mirror may be used.

The reference light reflecting means 140 is constituted by, for example, a reference mirror. As the reference mirror, for example, a corner cube prism, a plane mirror, or the like is applicable. Of these, from the viewpoint of parallelism of reflected light with incident light, it is preferable to use a corner cube prism. However, if the reference light can be reflected, it is not limited to the above-described one, and it may be constituted by, for example, a delay line or the like.

As the photodetector 160, it is preferable to use, for example, a photodiode in consideration of low cost and compactness. Specifically, it is configured by a PD (Photo Detector) using, for example, an Si photodiode, an InGaAs photodiode, a Ge photodiode, or the like. However, the present invention is not limited to the above-described one. For example, an avalanche photodiode, a photo-multiplier, or the like may be used as long as the interference between the measurement light from the temperature measurement object and the reference light from the reference light reflection means 140 can be measured The photodetector 160 may be formed. The detection signal of the photodetector 160 is input to the A / D converter 172 via the amplifier 171, converted into a digital signal, and processed by the controller 170.

The reference light from the first splitter 120 is transmitted through the optical fiber and the collimator 28 to the reference light irradiation position irradiated to the reference light reflection means 140. [ The first to fourth measurement lights from the second splitter 130 are measured by irradiating the semiconductor wafer W and the focus ring 29 via the optical fibers 20 to 23 and the collimators 24 to 27, To the light irradiation position.

The temperature measuring means 100 is configured such that the respective optical path lengths from the second splitter 130 to the temperature measurement object in the first to fourth measurement lights are different from each other. Concretely, for example, when the lengths of the optical fibers 20 to 23 are the same, for example, when the front end face of the collimators 24 to 27, that is, the measurement light irradiation position is located in the irradiation direction from the temperature measurement object And are arranged so as to be offset from each other in a substantially parallel direction. It is also possible to change the lengths of the optical fibers 20 to 23 without shifting the front end surfaces of the collimators 24 to 27 to change the lengths of the optical fibers 20 to 23 from the second splitter 130 in the first to fourth measurement lights, May be different from each other.

The difference between the optical path lengths from the second splitter 130 to the temperature measurement object in the first to fourth measurement lights is the difference between the first to fourth measured lights measured for each measurement point and the interference wave It is necessary to prevent them from overlapping each other. For example, when a low coherence light source is used as the light source 110, it is possible to prevent interference waves from overlapping if there is at least a difference in the length of each optical path from the coherence length of the interference wave. It is preferable that the difference in each optical path length is determined in consideration of the thickness of the temperature measurement object, the rate of change in thickness, the temperature range to be measured, the moving distance of the reference mirror, and the like. Specifically, for example, in the case of a silicon wafer having a thickness of about 0.7 mm, since the moving distance of the reference mirror in the temperature range from room temperature to about 200 ° C is about 0.04 mm, It is possible to prevent the interference waves of the respective measurement points from overlapping each other.

Accordingly, by merely scanning the reference light reflecting means 140 once, it is possible to detect interference waves at the measurement points irradiated with the first to fourth measurement lights at a time. Therefore, the time required for the temperature measurement can be extremely shortened.

4, the measuring light for temperature measurement irradiated from the temperature measurement windows 12 to 14 toward the semiconductor wafer W is reflected by the semiconductor wafer W And is reflected by the surface side of the semiconductor wafer W, and the interference wave between the reflected light and the reference light is detected.

5A, when the refractive index of the semiconductor wafer W is denoted by n and the thickness of the semiconductor wafer W is denoted by d, at a position apart from the semiconductor wafer W by a distance corresponding to nd, An interference wave (indicated by "lower" in the figure) of the reflected measurement light and an interference wave (indicated by "phase" in the figure) of the measurement light reflected from the surface side of the semiconductor wafer W are detected. Since the optical path lengths up to the respective measurement points are set to be different, a peak of the interference wave at each measurement point is detected at a position separated by a distance corresponding to the difference in optical path length as shown in Fig. 5A. 5A, the vertical axis represents the output of the photodetector, and the horizontal axis represents the movement distance of the mirror as the reference light reflection means. 5A, waveforms of the interference waves at the respective measurement points are indicated by solid lines, dotted lines, one-dot chain lines, and two-dotted chain lines in different linetypes.

When temperature measurement of the semiconductor wafer W or the like is performed by the temperature measurement means 100, the initial thickness measurement of the semiconductor wafer W or the like as the temperature measurement object is performed prior to the temperature measurement. At this time, a waveform as shown in Fig. 5A can be obtained, and the initial thickness of the semiconductor wafer W or the like can be obtained as the interval between the interference wave detection signals of "lower" and "upper" shown in Fig. 5A. The temperature of the semiconductor wafer W and the like is detected by a change in the thickness with respect to this initial thickness, that is, a change in the interval between the peaks of "lower" and "upper" shown in FIG.

In the temperature measuring means 100, the light from the light source 110 is incident on the first splitter 120, and can be divided into the measurement light and the reference light by the first splitter 120. The measurement light is divided into first through n-th measurement lights by the second splitter 130, and the measurement object such as a semiconductor wafer is irradiated with the measurement light at each measurement point, and the surface, Reflection.

On the other hand, the reference light is reflected by the reference light reflecting means 140. The respective reflected lights of the first to nth measurement lights are incident on the first splitter 120 via the second splitter 130 and are detected by the photodetector 160 together with the reflected light of the reference light.

By scanning the reference light reflecting means 140, it is possible to obtain an interference waveform as shown in Fig. 5A in which the vertical axis represents the output of the photodetector 160 and the horizontal axis represents the moving distance of the reference light reflecting means 140. [ Here, as the light source 110, a low coherence light source as described above is used. According to the low coherence light source, since the coherence length of the light from the light source 110 is short, interference usually occurs in a place where the optical path length of the measurement light coincides with the optical path length of the reference light. In other places, As well. Therefore, by changing the optical path length of the reference light by moving the reference light reflecting means 140, if there are other layers inside and outside the surface of the temperature measurement object, the respective layers are also reflected by the difference in refractive index Measurement light and reference light interfere.

Next, a method of measuring the temperature based on the interference wave between the measurement light and the reference light will be described in detail. As a temperature measurement method based on an interference wave, for example, there is a temperature conversion method using a change in optical path length based on a temperature change. Here, a method of temperature conversion using the positional deviation of the interference waveform will be described.

When the temperature measurement object such as the semiconductor wafer W is heated by the action of plasma or the like, the semiconductor wafer W expands and the refractive index changes. Therefore, the position of the interference waveform shifts before and after the temperature change, The width of the liver is changed. At this time, if there is a temperature change for each measurement point, the position of the interference waveform is shifted for each measurement point, and the width between the peaks of the interference waveform is changed. The temperature change can be detected by measuring the width between the peaks of the interference waveform for each of these measurement points. For example, in the case of the temperature measuring means 100 shown in Fig. 3, since the width of the peak of the interference waveform corresponds to the moving distance of the reference light reflecting means 140, the width of the peak of the interference waveform By measuring the moving distance of the reference light reflecting means 140, the temperature change can be detected.

When the thickness of the semiconductor wafer W is d and the refractive index is n, the deviation of the peak position with respect to the interference waveform depends on the linear expansion coefficient? Inherent in each layer with respect to the thickness d, (n) depends mainly on the temperature coefficient (?) of refractive index change inherent in each layer. It is also known that the temperature coefficient (?) Of refractive index change depends on the wavelength.

Therefore, the thickness d 'of the semiconductor wafer W after a temperature change at a certain measuring point P can be expressed by the following equation (1). In the equation (1),? T represents the temperature change of the measurement point,? Represents the linear expansion coefficient, and? Represents the temperature coefficient of the refractive index change. Further, d and n indicate the thickness and the refractive index at the measurement point P before the temperature change, respectively.

d'= d 占 (1 +? 占? T)

n '= n (1 +?? T) ... (One)

The optical path length of the measurement light passing through the measurement point P changes due to the temperature change as shown in the above equation (1). The optical path length is generally expressed as the product of the thickness d and the refractive index n. Therefore, let L be the optical path length of the measurement light passing through the measurement point P before the temperature change and L be the optical path length after the temperature at the measurement point is changed by DELTA T, (2).

L = d · n

L'= d'n '... (2)

Therefore, the difference (L'-L) before and after the temperature change of the optical path length of the measurement light at the measurement point is expressed by the following equation (3) when calculated in accordance with the above formulas (1) and (2) . Further, in the following expression (3), the micro term is omitted in consideration of? P? << alpha, alpha beta << beta.

L'-L = d'· n'- d · n = d · n · (α + β) · ΔT = L · (α + β) · ΔT 1 ... (3)

Here, the optical path length of the measurement light at each measurement point corresponds to the interval between the peaks of the interference waveform with the reference light. Therefore, if the linear thermal expansion coefficient? And the temperature coefficient? Of the change in refractive index are examined in advance, the interval between the peaks of the interference waveform with the reference light at each measurement point is measured, It can be converted to the temperature of the measurement point.

As described above, when the wavelength is converted from the interference wave to the temperature, the optical path length displayed between the peaks of the interference waveform changes in accordance with the linear expansion rate? And the temperature coefficient? Of the refractive index change. (?) and the temperature coefficient (?) of the refractive index change need to be examined in advance. The coefficient of linear expansion? Of the material including the semiconductor wafer W and the temperature coefficient? Of the refractive index change may generally depend on the temperature depending on the temperature range. For example, as for the coefficient of linear expansion (?), Generally, the temperature of the material does not change much in the temperature range of about 0 ° C to 100 ° C, so it may be regarded as constant. However, The higher the temperature, the larger the rate of change. In such a case, the temperature dependence can not be ignored. The temperature dependence of the refractive index change may also be negligible depending on the temperature range.

For example, in the case of silicon (Si) constituting the semiconductor wafer W, the coefficient of linear expansion? And the temperature coefficient? Of the refractive index change in the temperature range of 0 占 폚 to 500 占 폚 are, for example, It can be approximated by a quadratic curve. Since the coefficient of linear expansion? And the temperature coefficient? Of the refractive index change depend on the temperature, for example, the coefficient of linear expansion? And the temperature coefficient? If the temperature is converted in consideration of the value, the temperature can be converted into a more accurate temperature.

The temperature measurement method based on the interference wave between the measurement light and the reference light is not limited to the method described above. For example, a method using a change in absorption intensity based on a temperature change may be used. And the absorption intensity change based on the temperature change may be combined.

As described above, in the temperature measuring means 100, the temperature is basically measured based on the optical path length of the measurement light. If the optical path length is changed for reasons other than the temperature change of the temperature measurement object, And it becomes difficult to measure the temperature of the temperature measurement object with high accuracy. On the other hand, in the plasma processing apparatus 1 shown in Fig. 1, the temperature measurement windows 12 to 15 are provided on the stage 3, the upper side of the stage 3 is in a high vacuum atmosphere, Is an atmospheric pressure atmosphere. Therefore, the mounting table 3 is likely to generate vibration due to a pressure difference, a flow of the temperature control medium for cooling flowing through the electrostatic chuck 5, and the like. The distance between the stage 3 and the base plate 9 fluctuates and the distance between the collimators 24 to 27 and the semiconductor wafer W or the like And the optical path length of the temperature measuring means 100 is changed.

Therefore, in the present embodiment, the connecting member 30 for connecting the base plate 9 and the mounting table 3 (RF plate 4) is provided to suppress deformation and vibration of the mounting table 3 It is possible. This makes it possible to suppress the occurrence of a change in the optical path length in the temperature measuring means 100, suppress the generation of noise, and measure the temperature of the semiconductor wafer W with high precision . Since the temperature of the semiconductor wafer W or the like under plasma processing can be accurately measured, it is possible to perform the plasma processing with high precision by controlling the state of the plasma processing by feeding back the temperature measurement result.

6 is a graph showing the relationship between the position of 75 mm from the center of the semiconductor wafer W, the position of 128 mm, the position of 143 mm, the position of 158 mm ) Of the test sample. 6A is a graph showing the relationship between the pressure of helium gas for cooling supplied between the stage 3 and the back surface of the semiconductor wafer W in the range of 2000 Pa (15 Torr) / 5320 Pa (40 Torr) The former shows the pressure at the center portion and the latter the pressure at the peripheral portion). In this case, the temperature of the semiconductor wafer W rises from 20 占 폚 to 65 占 폚 to 75 占 폚 by igniting the plasma. On the other hand, FIG. 6B shows a case where the pressure of the helium gas is set to 0 Pa and the supply thereof is not performed. In this case, the temperature of the semiconductor wafer W exceeded 110 占 폚 at a position of 75 mm from the center of the wafer W and a position of 143 mm. The temperature of the focus ring did not change with the presence of helium gas.

As described above, the connecting member for connecting the base plate 9 and the mounting table 3 (RF plate 4) is not limited to the one shown in Fig. 1, and any shape may be used. Further, as shown in Fig. 7, a tubular member 30a formed in a cylindrical shape such as a hollow cylinder may be arranged so as to surround the optical path of each measurement light. With such a configuration, it is possible to suppress air flow and the like in the tubular member 30a, to maintain the state of the optical path of the measurement light in a good state, and to suppress the generation of noise due to air flow or the like. That is, as described above, since the air gap 10 between the RF plate 4 and the base plate 9 is atmospheric, fluctuation of the air influences the optical path, and measurement accuracy can be suppressed from being deteriorated.

Instead of the tubular member 30a, a cylindrical rod 30b made of a material such as quartz, sapphire, or the like may be used as shown in FIG.

The RF plate 4 and the electrostatic chuck 5 constituting the mounting table 3 are normally fastened only to the peripheral edge. Therefore, even if the RF plate 4 and the base plate 9 are connected by a connecting member, there is a possibility that the RF plate 4 and the electrostatic chuck 5 are deformed or vibrated as they are separated from each other. Therefore, as shown in Fig. 9, it is preferable that the RF plate 4 and the electrostatic chuck 5 are fastened to each other near the center of the portion of the power feed rod 6 or the like by a screw 30c or the like. The power feed rod 6 and the RF plate 4 are fastened by a fastening mechanism not shown.

Here, as described above, at a site where a structure is present below the RF plate 4 such as a central portion where the feed rod 6 is provided below the RF plate 4, It is difficult to provide the windows 12 to 15 and the like, and it is difficult to measure the temperature near the center of the semiconductor wafer W or the like. 10, a temperature measurement window 12a is disposed above the power supply rod 6 and two mirrors 40 are disposed on the lower surface of the RF plate 4, as shown in Fig. 10 One mirror is disposed at the lower end of the temperature measurement window 12a, that is, at the end of the temperature measurement window 12a which is in contact with the power supply rod 6, and the other mirror is disposed at the through hole 16 adjacent to the power supply rod 6. [ As shown in Fig.

According to such a configuration, by using a light beam passed through the temperature measurement window 12a, which is arranged so that the optical path of the measurement light is once bent in the horizontal direction and positioned at the upper portion of the power supply rod 6 by the two mirrors 40 or the like The temperature of the central portion of the semiconductor wafer W can be measured.

11, the optical path of the measurement light is once bent in the horizontal direction, using the integral prism 42 as shown in Fig. 12, It is also possible to measure the temperature in the vicinity of the center of the semiconductor wafer W from the temperature measurement window 12a or the like arranged so as to be positioned above the semiconductor wafer W. [ This configuration can be similarly applied to the case of measuring the temperature of the peripheral portion of the mounting table 3 on which the focus ring 29 is disposed, for example. The case of measuring the temperature of the semiconductor wafer W from the counter electrode 11 side can also be applied in the same manner.

The collimators 24 to 27 are fixed to the base plate 9 as in the embodiment shown in Fig. 13, 13, it is fixed to the RF plate 4). With such a configuration, the collimators 24 to 27 and the semiconductor wafer W, which is the object of temperature measurement, can be brought closer to each other, and the fluctuation of the optical path length of the measurement light due to the deformation or vibration of the mount table 3 can be further suppressed . In this case, the fluctuation of the air in the gap 10 between the RF plate 4 and the base plate 9 affects the optical path, so that the measurement accuracy does not deteriorate.

13 shows a case where the collimators 24 to 27 are fixed to the RF plate 4. It is also possible to adopt a configuration in which the collimators 24 to 27 are fixed to the electrostatic chuck 5. [ With such a configuration, fluctuation of the optical path length of measurement light due to deformation or vibration of the mounting table 3 can be further suppressed. However, in this case, the ease of maintenance such as adjustment of the optical path by the collimators 24 to 27 is impaired.

As shown in Fig. 1, an upper electrode 11 is provided in the vacuum chamber 2 so as to face the loading table 3 above the loading table 3. As shown in Fig. In some cases, a cell 11a made of a material capable of transmitting infrared rays such as silicon is disposed on the surface of the upper electrode 11 opposed to the mounting table 3. In this case, as shown in Fig. 14, the cell 11a is moved from the temperature measurement windows 12 to 14 (and the temperature measurement window 15) through the semiconductor wafer W (and the focus ring 29) It is possible to measure the temperature of the cell 11a by irradiating measurement light to the cell 11a and measuring the reflected light from the lower side (i.e., the surface) and the upper side (i.e., the back side)

In this case, when the thickness of the semiconductor wafer W is d, the refractive index is n, the distance from the semiconductor wafer W to the cell 11a is L, the thickness of the cell 11a is D, and the refractive index is N, 5B, after the interference signal is detected from the lower side of the semiconductor wafer W, the interference signal at the lower side of the cell 11a at a position distant from L + Is detected. After an interference signal from the lower side of the cell 11a is detected, an interference signal from the upper side of the cell 11a is detected at a position distant from the cell 11a by the distance ND. The temperature of the cell 11a can be measured from the change in the distance between the interference signal from the lower side of the cell 11a and the interference signal from the upper side.

When the semiconductor wafer W is removed from the mounting table 3 as shown in Fig. 15, as shown in Figs. 16A and 16B, when the semiconductor wafer W is absent (Fig. 16A) In the case where the wafer W is present (Fig. 16B), since the interference position of the reflected light from the cell 11a is shifted by (n-1) d0, it is necessary to change the initial position.

17 is a flow chart showing the procedure for measuring the temperature of the cell 11a. 17, first, the temperature of the mount table and the cell are set (step 170), and the initial position X0 of the surface of the cell 11a and the initial position X0 of the cell 11a in the state where the semiconductor wafer W is not carried The thickness D0 is measured (step 171).

Next, a step of setting the initial position of the surface of the cell 11a to X1 is executed (step 172).

Next, the semiconductor wafer W is carried in and placed on the stage 3 (step 173), and the initial position x0 and the initial thickness d0 of the lower side of the semiconductor wafer W are measured 174).

Thereafter, temperature measurement is started with the initial position of the cell 11a being X1, the initial thickness being D0, the initial position of the lower side of the semiconductor wafer W being x0, and the initial thickness being d0 (step 175) .

18A and 18B show an example of a result of measuring the temperature (Fig. 18A) of the cell 11a and the temperature 18b of the focus ring 29 during the plasma processing by the above-described process. Shows the results measured by the above-described process when three wafers are sequentially plasma-treated. As shown in Fig. 18, the temperature of the cell 11a rises to 220 DEG C or higher. Further, the temperature of the focus ring 29 is about 80 캜 to 90 캜.

It is possible to measure not only the temperature of the semiconductor wafer W but also the temperatures of the cell 11a and the focus ring 29 as described above and thus it becomes possible to control the plasma processing process more precisely and densely, It is possible to execute plasma processing with higher accuracy. The consumption amount of the cell 11a and the focus ring 29 can also be monitored at the same time so that it is possible to know the replacement timing of the cell 11a and the focus ring 29. Further, The process of the plasma process may be controlled in accordance with the degree of consumption of the plasma 29. In this case, it is possible to use the cell 11a and the focus ring 29 over a longer period of time, thereby reducing the running cost due to prolonged life thereof and improving the productivity by improving the operating rate of the apparatus It is possible.

Figs. 19A to 19H show the configuration of a modification of the temperature measuring windows 12 to 15. Fig. In the window for temperature measurement shown in Fig. 19A, a projection 52b protruding inward is provided at the upper end of the sleeve 52, and the window member 53 is supported by the projection 52b. Further, a protective film 57 is provided up to the upper side of the sleeve 52.

The window for temperature measurement shown in Fig. 19B has a structure in which the sleeve 52 does not have the projecting portion 52b described above, and the periphery of the upper end of the window member 53 contacts the protective film 57. Fig. The temperature measurement window shown in Fig. 19C is different from the temperature measurement window shown in Fig. 19C in that the sleeve 52 does not have the projection 52b and the protective film 57 is not in contact with the peripheral edge of the upper end of the window member 53, And the upper end of the window member 53 extends to the surface of the electrostatic chuck 5.

19D has a structure in which the upper end of the sleeve 52 provided with the projecting portion 52b extends to the surface of the electrostatic chuck 5 similarly to the case of Fig. 19A. The temperature measurement window shown in Fig. 19E has a structure in which the sleeve 52 having no projecting portion 52b is used as in the case of Fig. 19B, and the upper end thereof extends to the surface of the electrostatic chuck 5.

19F has a structure in which the upper end of the sleeve 52 provided with the protruding portion 52b is covered with the protective film 57 as in the case of Fig. 19A. The temperature measurement window shown in Fig. 19G uses the sleeve 52 without the protruding portion 52b as in the case of Fig. 19B and the upper end of the sleeve 52 and the window member 53 is covered with the protective film 57, As shown in FIG.

19H, a sleeve 52 having no projection 52b is used and the upper ends of the sleeve 52 and the opening 58 are fixed to the protective film 57 And the window member 53 is not provided in the sleeve 52. In this case, the vacuum is cut off by the protective film 57 provided on the surface, and it is necessary that the protective film 57 is made of a material having strength capable of withstanding the pressure difference.

Further, the temperature measurement windows 12 to 15 are not limited to the above-described configuration, and various modifications are possible. For example, as shown in Figs. 20A and 20B, an end portion 52c having a larger diameter toward the outside is provided at the upper end of the sleeve 52, and a window 52c having a flange portion 53b protruding outward at the upper end The member 53 may be supported by contacting the end portion 52c with the flange portion 53b. In this case, as shown in Fig. 20B, the window member 53 can be detached from the surface side of the electrostatic chuck 5, and, for example, when the window member 53 is contaminated, damaged, Can be easily exchanged. In Fig. 20, reference numeral 54 denotes an O-ring for a vacuum seal.

In each of the above embodiments, as shown in Fig. 1 and the like, an RF plate 4 to which the mounting table 3 is made of a conductive material and to which high-frequency power is applied, And an electrostatic chuck 5 for adsorbing the wafer W are described. However, for example, as shown in Fig. 21, the mounting table 3a is also applicable to the plasma processing apparatus 1 in which the RF plate 4a and the electrostatic chuck 5a are integrated with each other It is possible to do. In this case, as shown in Fig. 22, a plasma processing apparatus 1 (see Fig. 22) in which an insulating material 3b is provided on a lower part of a mounting table 3a having a structure in which an RF plate 4a and an electrostatic chuck 5a are integrated ) Can be applied in the same manner. In FIGS. 21 and 22, the same reference numerals are assigned to the parts corresponding to those in FIG. 1, and a duplicate description will be omitted.

Next, the configuration of a modification of the present invention will be described with reference to Figs. 23 and 24. Fig. Fig. 23 is a diagram showing a schematic configuration viewed from the side of the modification example, and Fig. 24 is a diagram showing a schematic configuration seen from above. In this modified example, it is the same as the above-described embodiment that the temperature measuring means is constructed in the same manner as the temperature measuring means 100 shown in Fig. 3 and performs temperature measurement using the light from the light source 110 .

23 and 24, in this modified example, a window portion (window for temperature measurement) 210 capable of transmitting light to the inside and the outside of the vacuum chamber 2 is provided on the side wall portion of the vacuum chamber 2 . Further, a prism 220 as an optical path changing means is provided on the focus ring 29. The prism 220 is fixed to the focus ring 29 by a frame 221 made of quartz. It is preferable that the prism 220 is installed at a position close to the window part 210 and it is most preferable that the prism 220 is placed on the focus ring 29 closest to the window part 210. The optical path changing means is not limited to the prism 220, and any optical path changing means may be used as long as it can change the optical path of the measuring light efficiently.

A collimator 27 to which the optical fiber 23 is connected is provided outside the window portion 210 and the measurement light from a light source not shown passes through the optical fiber 23 and is emitted from the collimator 27 , And enters the vacuum chamber (2) through the window portion (210). As shown by arrow A in FIG. 23, the incident measuring light is changed to an optical path downward substantially at right angles by the prism 220, and is irradiated to the focus ring 29. The measurement light reflected by the focus ring 29 The light is changed to the optical path in the horizontal direction at a substantially right angle by the prism 220 and returned to the window part 210 to be incident on the collimator 27. Then, the measurement light is sent from the collimator 27 to the optical detector (not shown) of the temperature detection means through the optical fiber 23, and the temperature is measured in the same manner as in the above-described embodiment. According to this configuration, since the measurement light does not pass through the atmosphere, the fluctuation of the air affects the optical path, so that the measurement accuracy does not deteriorate. In addition, if the window for detecting the end point of etching is commonly used as in the case of the above-described embodiment, the window part 210 needs to be newly provided in the vacuum chamber 2 And the temperature of the focus ring 29 can be simply measured.

A plurality of the prisms 220 may be provided to measure the temperature of the focus ring 29 at a plurality of positions. In this case, a plurality of optical fibers 23 and a set of collimators 27 may be provided outside one window portion 210, and the measurement light may be irradiated to the other prism 220 by changing the angle. The window portions 210 may be provided at two positions, for example, at intervals of 180 degrees, and the temperature of the portion of the window ring 210 spaced by 180 degrees from the focus ring 29 may be measured.

1 and the like, the temperature of the semiconductor wafer W is measured at three points and the temperature of the focus ring 29 is measured at one point. However, only the temperature of the focus ring 29 is measured, It may be measured as in the above modification. In this modified example, since optical path changing means such as the prism 220 must be provided on the focus ring 29, it is necessary to provide optical path changing means such as a prism 220, For example, it is mainly used in the evaluation stage before manufacturing the product.

While the preferred embodiments of the present invention have been described with reference to the accompanying drawings, it is needless to say that the present invention is not limited to these examples. It will be understood by those skilled in the art that various modifications and variations are considered within the scope of the appended claims and that they are obviously also within the technical scope of the present invention.

1: Plasma processing device 2: Vacuum chamber
3: Mounting table 4: RF plate
5: Electrostatic chuck 6: Feed rod
7: Baffle plate 8: Exhaust space
9: base plate 10: air gap
11: Opposite electrodes 12 to 15: Window for temperature measurement
20 to 23: Optical fiber 24 to 27: Collimator
29: focus ring 30: connecting member
W: Semiconductor wafer

Claims (20)

A vacuum chamber for receiving and processing the substrate by plasma; A mount table provided in the vacuum chamber and on which a substrate is mounted; A base plate provided below the mount table and spaced apart from the mount table; A reference light reflecting means for reflecting the reference light from the splitter; and an optical path length changing means for changing the optical path length of the reference light reflected from the reference light reflecting means, An optical fiber for irradiating the measurement light onto the substrate, a collimator provided at an exit portion of the optical fiber, and a collimator for measuring the interference between the measurement light reflected from the substrate and the reference light reflected from the reference light reflection means. And a temperature measuring means having a detector, wherein a space above the mounting table is in a vacuum atmosphere, and a space between the mounting table and the base plate is a normal pressure atmosphere,
Wherein the measurement window is optically communicated with the upper surface and the lower surface of the mount table so as to allow the measurement light to pass therethrough and a hermetically sealed temperature measurement window is provided,
Wherein a member for connecting the mounting table to the base plate is provided at an interval between the mounting table and the base plate,
Further, the collimator may be fixed at a position corresponding to the temperature measurement window of the base plate,
A rod or a hollow cylindrical body through which the measurement light can pass is provided in the optical path of the measurement light between the mount table and the base plate,
And the temperature of the substrate can be measured by the temperature measuring means from the window for temperature measurement
Plasma processing apparatus. The method according to claim 1,
A mirror or a prism for bending the optical path of the measurement light toward the side and vertically is provided in the mount so that the temperature of the center of the substrate located above the power feed rod connected to the center of the mount can be measured doing
Plasma processing apparatus. A vacuum chamber for receiving and processing the substrate by plasma; A mount table provided in the vacuum chamber and on which a substrate is mounted; A base plate provided below the mount table and spaced apart from the mount table; A reference light reflecting means for reflecting the reference light from the splitter; and an optical path length changing means for changing the optical path length of the reference light reflected from the reference light reflecting means, An optical fiber for irradiating the measurement light onto the substrate, a collimator provided at an exit portion of the optical fiber, and a collimator for measuring the interference between the measurement light reflected from the substrate and the reference light reflected from the reference light reflection means. And a temperature measuring means having a detector, wherein a space above the mounting table is in a vacuum atmosphere, and a space between the mounting table and the base plate is a normal pressure atmosphere,
Wherein the measurement window is optically communicated with the upper surface and the lower surface of the mount table so as to allow the measurement light to pass therethrough and a hermetically sealed temperature measurement window is provided,
Wherein a member for connecting the mounting table to the base plate is provided at an interval between the mounting table and the base plate,
Further, the collimator may be fixed at a position corresponding to the temperature measurement window of the base plate,
The temperature of the substrate can be measured by the temperature measuring means from the window for temperature measurement,
It is also possible to provide a mirror or prism for bending the optical path of the measurement light sideways and vertically in the mount so that the temperature of the center of the substrate located above the power supply rod connected to the center of the mount can be measured Featured
Plasma processing apparatus. 4. The method according to any one of claims 1 to 3,
Wherein,
An RF plate made of a conductive material to which high-frequency power is applied,
And an electrostatic chuck provided on the RF plate for adsorbing the substrate.
Plasma processing apparatus. 5. The method of claim 4,
Characterized in that the RF plate and the electrostatic chuck are fixed at both the peripheral portion and the central portion
Plasma processing apparatus. 4. The method according to any one of claims 1 to 3,
Characterized in that the mounting table is configured such that an RF plate made of a conductive material to which high-frequency power is applied and an electrostatic chuck for adsorbing the substrate are integrally formed
Plasma processing apparatus. A vacuum chamber for receiving and processing the substrate by plasma; A mount table provided in the vacuum chamber and on which a substrate is mounted; A base plate provided below the mount table and spaced apart from the mount table; A reference light reflecting means for reflecting the reference light from the splitter; and an optical path length changing means for changing the optical path length of the reference light reflected from the reference light reflecting means, An optical fiber for irradiating the measurement light onto the substrate, a collimator provided at an exit portion of the optical fiber, and a collimator for measuring the interference between the measurement light reflected from the substrate and the reference light reflected from the reference light reflection means. And a temperature measuring means having a detector, wherein a space above the mounting table is in a vacuum atmosphere, and a space between the mounting table and the base plate is a normal pressure atmosphere,
Wherein the measurement window is optically communicated with the upper surface and the lower surface of the mount table so as to allow the measurement light to pass therethrough and a hermetically sealed temperature measurement window is provided,
Fixing the collimator to a position corresponding to the temperature measurement window of the mounting table,
And the temperature of the substrate can be measured by the temperature measuring means from the window for temperature measurement
Plasma processing apparatus. 8. The method of claim 7,
Wherein the mounting table comprises an RF plate made of a conductive material to which high frequency power is applied, and an electrostatic chuck provided on the RF plate for adsorbing the substrate,
Characterized in that the collimator is fixed to the RF plate or the electrostatic chuck
Plasma processing apparatus. 8. The method of claim 7,
The mounting table is configured such that an RF plate made of a conductive material to which high frequency power is applied and an electrostatic chuck for adsorbing the substrate are integrated,
And the collimator is fixed to the RF plate.
Plasma processing apparatus. 8. The method of claim 7,
Wherein the temperature measuring means includes a second splitter for dividing the measurement light from the splitter into n first to n-th measurement lights, and the temperature of the plurality of portions is measured by a plurality of measurement lights from the second splitter Characterized in that it is possible to measure
Plasma processing apparatus. 8. The method of claim 7,
An opposing electrode is provided in the vacuum chamber so as to face the mounting table and the temperature measuring means is capable of measuring the temperature of the portion of the counter electrode through the temperature measurement window and the substrate of the object to be mounted Characterized by
Plasma processing apparatus. A vacuum chamber for receiving and processing the substrate by plasma; A mount table provided in the vacuum chamber and on which a substrate is mounted; A base plate provided below the mount table and spaced apart from the mount table; A reference light reflecting means for reflecting the reference light from the splitter; and an optical path length changing means for changing the optical path length of the reference light reflected from the reference light reflecting means, An optical fiber for irradiating the measurement light onto the substrate, a collimator provided at an exit portion of the optical fiber, and a collimator for measuring the interference between the measurement light reflected from the substrate and the reference light reflected from the reference light reflection means. And a temperature measuring means having a detector, wherein a space above the mounting table is in a vacuum atmosphere, and a space between the mounting table and the base plate is a normal pressure atmosphere,
Wherein the measurement window is optically communicated with the upper surface and the lower surface of the mount table so as to allow the measurement light to pass therethrough and a hermetically sealed temperature measurement window is provided,
Wherein a member for connecting the mounting table to the base plate is provided at an interval between the mounting table and the base plate,
Further, the collimator may be fixed at a position corresponding to the temperature measurement window of the base plate,
The temperature of the substrate can be measured by the temperature measuring means from the window for temperature measurement,
An opposite electrode is provided in the vacuum chamber so as to face the mounting table. The temperature measuring means is capable of measuring the temperature of the portion of the counter electrode through the temperature measurement window and the substrate of the mounting object Characterized in that
Plasma processing apparatus. delete delete delete delete delete delete delete delete

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